A chip supply apparatus is an apparatus of carrying out an operation of exfoliating a chip from a wafer sheet by pushing up a chip pasted on an elongatable and contractable wafer sheet from a lower side of a wafer sheet and adsorbing the chip from an upper side by a nozzle to supply to a supply object of a board or the like. The chip pasted on the wafer sheet is configured by forming a semiconductor wafer into individual pieces by dicing, an interval between the chips contiguous to each other is narrow, it is difficult to exfoliate only one chip, and therefore, in the chip supply apparatus, the interval between the chips is widened by exerting a tension to the wafer sheet (refer to Patent References 1 and 2).
Patent Reference 1: JP-A-2-231740
Patent Reference 2: JP-A-5-29440
When the tension is interrupted from exerting to the wafer sheet exerted with the tension once, an elongation remains, and the wafer sheet is brought into a state of being slackened on an inner side of a wafer ring of holding an outer periphery of the wafer sheet. In a background art, in interchanging the wafer sheet finished to use the chip, the wafer sheet is detached from the chip supply apparatus having a tension ring of exerting the tension to the wafer sheet, a new wafer sheet is molded in place thereof, however, when the wafer sheet brought into a state in which a chip remains, there is a possibility that the chips contiguous to each other are brought into contact with each other by slacking the wafer sheet, and a brittle edge or corner portion is destructed. Further, as a different problem, in an apparatus such as a multi-chip bonder of mounting a variety of parts to a board, the wafer sheet is interchanged at a high frequency, and therefore, a time period of mounting and detaching the wafer sheet to and from the chip supply apparatus is required at every time of interchange and a productivity is reduced.